Malicious PDF — malware analysis report

Static analysis result for SHA-256 1c8508b1abb87acd…

MALICIOUS

PDF

91.4 KB Created: 2021-07-02 08:37:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 77cd532085435cd71373c8fccba445ef SHA-1: c94689594ae1d3b3fc7e0e6fdae9b4c3eff54d1a SHA-256: 1c8508b1abb87acd9c98a922ac39c323a9ceb94af60ae8317473b52c69de1974
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was detected as malicious by ML classifiers and ClamAV, indicating a phishing or malware distribution attempt. It functions as a link farm, directing users to numerous external URLs, some of which host further PDF files, likely to facilitate credential harvesting or the download of additional malicious content. No scripts were extracted from this sample, but the presence of external links suggests an attempt to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://crewmak.ru/uplcv?utm_term=safari+is+a+web+browser
    • http://hungbuloon.com/media/ftp/file/52247650609.pdf
    • http://infrabud.eu/fckpliki/file/rapufodofamidamovewereka.pdf
    • http://svsteinfurth.de/radsportfiles/file/jefitixaxid.pdf
    • http://www.guaitoli.eng.br/wp-content/plugins/formcraft/file-upload/server/content/files/160846ccdf0b71---vuwifedojez.pdf
    • http://fbchitchcock.org/clients/8/8b/8bdff38a390027835eb24981312b950c/File/wirowitusazesujen.pdf
    • http://asahiru-ban.com/files/files/61557640044.pdf
    • https://marljivo.hr/userfiles/file/7744344023.pdf
    • https://www.movingwithmagna.com/wp-content/plugins/super-forms/uploads/php/files/f10941f9cc9b9a0963d5e66a0e6c2b3d/xunaloxug.pdf
    • http://seigyobannkaigaikikaku.com/ckfinder/userfiles/files/nejasokero.pdf
    • https://kcharp.com/ckfinder/userfiles/files/roromiwapupafijanuwok.pdf
    • https://www.golddustdental.com/wp-content/plugins/formcraft/file-upload/server/content/files/16083748bf16cc---43124866841.pdf
    • https://joyfool.art/wp-content/plugins/super-forms/uploads/php/files/17b2e0f1d2e02906c55681ab30692de0/75250997864.pdf
    • http://www.circoloaletrium.it/wp-content/plugins/formcraft/file-upload/server/content/files/160ab169d7ef8a---betafugur.pdf
    • https://refour.eu/wp-content/plugins/super-forms/uploads/php/files/b9a0abbe3d1c9df0e197f0a17cc57a7e/vaxidalezad.pdf
    • http://frederickfollows.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160ceeaa66598d---vixese.pdf
    • https://www.vibrationmonitoring.asia/wp-content/plugins/formcraft/file-upload/server/content/files/160ad7b26dcfd1---kinize.pdf
    • https://www.isnb.co.uk/wp-content/plugins/super-forms/uploads/php/files/fcc4ccc31fae7bd2d00ca3931ef2df6c/89775924109.pdf
    • https://topplene.com/upload/ckfinder_temp/files/20210619192902.pdf
    • http://a-range.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160ca15a984493---tobinogalag.pdf
    • http://bilagroup.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a1376e5162e---wavokejiviguxuji.pdf
    • https://vallejardin.com/wp-content/plugins/super-forms/uploads/php/files/c884c76774be4ee022c457fefc83353c/19238119676.pdf
    • http://www.linkkorea.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/16070c527c5ab1---malusajumolivagog.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0001025c.bin
ca9d961d0886b9f4614325a7eeaa8bec832f8b385e85359a68d85b7fda986a32
pdf-font-stream PDF embedded font (sfnt) at offset 0x1025C 10260 bytes
font_01_sfnt_off0001199d.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1199D 16792 bytes
font_02_sfnt_off000131af.bin
619a788a67a9956750cafbe2521a0664000b33e54d0a7bfa9274ff2f7eb3b846
pdf-font-stream PDF embedded font (sfnt) at offset 0x131AF 17828 bytes